Shielding features for ultrasonic blade of a surgical instrument

ABSTRACT

An apparatus comprises a body, a shaft assembly, an end effector, and a shield member. The shaft assembly extends distally from the body. The end effector is located at a distal end of the shaft assembly. The end effector comprises an ultrasonic blade and a clamp arm. The ultrasonic blade is configured to vibrate at an ultrasonic frequency. The clamp arm is movable toward the ultrasonic blade to compress tissue against the ultrasonic blade. The shield member is selectively movable from a first position to a second position in response to movement of the clamp arm toward the ultrasonic blade. The shield member is configured cover at least a first portion of the ultrasonic blade in the first position. The shield member is configured to uncover the first portion of the ultrasonic blade in the second position.

PRIORITY

This application claims priority to U.S. Provisional Patent App. No.61/908,920, entitled “Heat Management for Ultrasonic SurgicalInstrument,” filed Nov. 26, 2013, the disclosure of which isincorporated by reference herein.

BACKGROUND

A variety of surgical instruments include an end effector having a bladeelement that vibrates at ultrasonic frequencies to cut and/or sealtissue (e.g., by denaturing proteins in tissue cells). These instrumentsinclude piezoelectric elements that convert electrical power intoultrasonic vibrations, which are communicated along an acousticwaveguide to the blade element. The precision of cutting and coagulationmay be controlled by the surgeon's technique and adjusting the powerlevel, blade edge, tissue traction and blade pressure.

Examples of ultrasonic surgical instruments include the HARMONIC ACE®Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONICFOCUS® Ultrasonic Shears, and the HARMONIC SYNERGY® Ultrasonic Blades,all by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. Further examplesof such devices and related concepts are disclosed in U.S. Pat. No.5,322,055, entitled “Clamp Coagulator/Cutting System for UltrasonicSurgical Instruments,” issued Jun. 21, 1994, the disclosure of which isincorporated by reference herein; U.S. Pat. No. 5,873,873, entitled“Ultrasonic Clamp Coagulator Apparatus Having Improved Clamp Mechanism,”issued Feb. 23, 1999, the disclosure of which is incorporated byreference herein; U.S. Pat. No. 5,980,510, entitled “Ultrasonic ClampCoagulator Apparatus Having Improved Clamp Arm Pivot Mount,” filed Oct.10, 1997, the disclosure of which is incorporated by reference herein;U.S. Pat. No. 6,325,811, entitled “Blades with Functional BalanceAsymmetries for use with Ultrasonic Surgical Instruments,” issued Dec.4, 2001, the disclosure of which is incorporated by reference herein;U.S. Pat. No. 6,773,444, entitled “Blades with Functional BalanceAsymmetries for Use with Ultrasonic Surgical Instruments,” issued Aug.10, 2004, the disclosure of which is incorporated by reference herein;and U.S. Pat. No. 6,783,524, entitled “Robotic Surgical Tool withUltrasound Cauterizing and Cutting Instrument,” issued Aug. 31, 2004,the disclosure of which is incorporated by reference herein.

Still further examples of ultrasonic surgical instruments are disclosedin U.S. Pub. No. 2006/0079874, entitled “Tissue Pad for Use with anUltrasonic Surgical Instrument,” published Apr. 13, 2006, the disclosureof which is incorporated by reference herein; U.S. Pub. No.2007/0191713, entitled “Ultrasonic Device for Cutting and Coagulating,”published Aug. 16, 2007, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2007/0282333, entitled “UltrasonicWaveguide and Blade,” published Dec. 6, 2007, the disclosure of which isincorporated by reference herein; U.S. Pub. No. 2008/0200940, entitled“Ultrasonic Device for Cutting and Coagulating,” published Aug. 21,2008, the disclosure of which is incorporated by reference herein; U.S.Pub. No. 2009/0105750, entitled “Ergonomic Surgical Instruments,”published Apr. 23, 2009, the disclosure of which is incorporated byreference herein; U.S. Pub. No. 2010/0069940, entitled “UltrasonicDevice for Fingertip Control,” published Mar. 18, 2010, the disclosureof which is incorporated by reference herein; and U.S. Pub. No.2011/0015660, entitled “Rotating Transducer Mount for UltrasonicSurgical Instruments,” published Jan. 20, 2011, the disclosure of whichis incorporated by reference herein; and U.S. Pub. No. 2012/0029546,entitled “Ultrasonic Surgical Instrument Blades,” published Feb. 2,2012, the disclosure of which is incorporated by reference herein.

Some of ultrasonic surgical instruments may include a cordlesstransducer such as that disclosed in U.S. Pub. No. 2012/0112687,entitled “Recharge System for Medical Devices,” published May 10, 2012,the disclosure of which is incorporated by reference herein; U.S. Pub.No. 2012/0116265, entitled “Surgical Instrument with Charging Devices,”published May 10, 2012, the disclosure of which is incorporated byreference herein; and/or U.S. Pat. App. No. 61/410,603, filed Nov. 5,2010, entitled “Energy-Based Surgical Instruments,” the disclosure ofwhich is incorporated by reference herein.

Additionally, some ultrasonic surgical instruments may include anarticulating shaft section. Examples of such ultrasonic surgicalinstruments are disclosed in U.S. Pub. No. 2014/0005701, entitled“Surgical Instruments with Articulating Shafts,” published Jan. 2, 2014,the disclosure of which is incorporated by reference herein; and U.S.Pub. No. 2014/0114334, entitled “Flexible Harmonic Waveguides/Blades forSurgical Instruments,” published Apr. 24, 2014 the disclosure of whichis incorporated by reference herein.

While several surgical instruments and systems have been made and used,it is believed that no one prior to the inventors has made or used theinvention described in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim this technology, it is believed this technologywill be better understood from the following description of certainexamples taken in conjunction with the accompanying drawings, in whichlike reference numerals identify the same elements and in which:

FIG. 1 depicts a side elevational view of an exemplary surgicalinstrument;

FIG. 2 depicts a perspective view of the end effector of the instrumentof FIG. 1, in an open configuration;

FIG. 3A depicts a side cross-sectional view of the end effector of FIG.2, in the open configuration;

FIG. 3B depicts a side cross-sectional view of the end effector of FIG.2, in a closed configuration;

FIG. 4 depicts a perspective view of another exemplary surgicalinstrument;

FIG. 5 depicts a side elevational view of the end effector of theinstrument of FIG. 4, in a closed configuration;

FIG. 6A depicts a perspective view of the end effector of FIG. 5, in anopen configuration;

FIG. 6B depicts a perspective view of the end effector of FIG. 5, in aclosed configuration;

FIG. 7A depicts a side elevational view of the distal portion of anexemplary alternative surgical instrument, with a translating heatshield in a proximal position;

FIG. 7B depicts a side elevational view of the distal portion of theinstrument of FIG. 7A, with the heat shield in a distal position;

FIG. 8 depicts a cross-sectional end view of the heat shield of FIG. 7Apositioned about the ultrasonic blade of the instrument of FIG. 7A;

FIG. 9A depicts a perspective view of an exemplary alternative endeffector, in an open configuration, with a heat shield engaging theultrasonic blade;

FIG. 9B depicts a perspective view of the end effector of FIG. 9A, in aclosed configuration, with the heat shield deflected away from theultrasonic blade;

FIG. 10 depicts a perspective view of an exemplary alternative endeffector, in an open configuration, with dual heat shields engaging theultrasonic blade;

FIG. 11 depicts a perspective view of an exemplary ultrasonic bladeshield;

FIG. 12 depicts a perspective view of an end effector with the bladeshield of FIG. 11 fitted on the ultrasonic blade;

FIG. 13 depicts a perspective view of the end effector of FIG. 12, witha distal portion of the end effector shown in cross section;

FIG. 14 depicts a perspective view of another exemplary alternativeultrasonic blade shied;

FIG. 15 depicts a perspective view of an end effector with the bladeshield of FIG. 14 fitted on the ultrasonic blade;

FIG. 16 depicts a perspective view of the end effector of FIG. 15, witha distal portion of the end effector shown in cross section;

FIG. 17 depicts a perspective view of an end effector with an exemplaryalternative ultrasonic blade shield fitted on the ultrasonic blade;

FIG. 18 depicts a perspective view of an ultrasonic blade with anotherexemplary alternative blade shield;

FIG. 19 depicts a cross-sectional end view of the blade and shield ofFIG. 18, taken along line 19-19 of FIG. 18;

FIG. 20 depicts a cross-sectional end view of the blade and shield ofFIG. 18, taken along line 19-19 of FIG. 18, after the shield has beenruptured through use of the end effector;

FIG. 21A depicts a cross-sectional end view of an ultrasonic blade withanother exemplary alternative blade shield;

FIG. 21B depicts a cross-sectional end view of the blade and shield ofFIG. 21A, with a clamp pad clamping against the blade;

FIG. 22 depicts a cross-sectional end view of an ultrasonic blade withanother exemplary alternative blade shield;

FIG. 23 depicts a perspective view of the instrument of FIG. 4 with anexemplary clamp arm shield secured to the clamp arm;

FIG. 24 depicts a perspective view of the instrument of FIG. 4 with theclamp arm shield of FIG. 23 separated from the clamp arm;

FIG. 25 depicts a perspective view of the shield of FIG. 23;

FIG. 26 depicts another perspective view of the shield of FIG. 23;

FIG. 27 depicts a cross-sectional view of the shield of FIG. 23, takenalong line 27-27 of FIG. 25;

FIG. 28 depicts a perspective view of the clamp arm of the instrument ofFIG. 4 with the shield of FIG. 23 secured thereto;

FIG. 29 depicts a cross-sectional view of the clamp arm of theinstrument of FIG. 4 with the shield of FIG. 23 secured thereto;

FIG. 30 depicts a perspective view of another exemplary alternative endeffector, with a clamp arm shield secured to the clamp arm;

FIG. 31 depicts a cross-sectional end view of the end effector and clamparm shield of FIG. 30;

FIG. 32 depicts a side elevational view of the end effector and clamparm shield of FIG. 30, with the clamp arm shield shown in cross-section;

FIG. 33 depicts a perspective view of an exemplary clamp arm sleeve;

FIG. 34A depicts an exploded perspective view of an exemplary assemblyincluding the clamp arm sleeve of FIG. 33 separated from the clamp armof the end effector of FIG. 5;

FIG. 34B depicts an exploded perspective view of the assembly of FIG.34A including the clamp arm sleeve of FIG. 33 joined to the clamp arm ofthe end effector of FIG. 5;

FIG. 34C depicts a perspective view of the assembly of FIG. 34Aincluding the clamp arm sleeve of FIG. 33 joined to the clamp arm of theend effector of FIG. 5, with the clamp pad further joined to the clamparm;

FIG. 35 depicts a cross-sectional end view of the assembly of FIG. 34A;

FIG. 36A depicts a perspective view of another exemplary alternative endeffector, in an open configuration;

FIG. 36B depicts a perspective view of the end effector of FIG. 36A, ina closed configuration; and

FIG. 37 depicts a bottom plan view of the end effector of FIG. 36A, inthe closed configuration.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the technology may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presenttechnology, and together with the description serve to explain theprinciples of the technology; it being understood, however, that thistechnology is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,embodiments, and advantages of the technology will become apparent tothose skilled in the art from the following description, which is by wayof illustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Thefollowing-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

For clarity of disclosure, the terms “proximal” and “distal” are definedherein relative to a human or robotic operator of the surgicalinstrument. The term “proximal” refers the position of an element closerto the human or robotic operator of the surgical instrument and furtheraway from the surgical end effector of the surgical instrument. The term“distal” refers to the position of an element closer to the surgical endeffector of the surgical instrument and further away from the human orrobotic operator of the surgical instrument.

I. Exemplary Ultrasonic Surgical Instrument

FIGS. 1-6B illustrate exemplary ultrasonic surgical instruments (10,100). At least part of each instrument (10, 100) may be constructed andoperable in accordance with at least some of the teachings of U.S. Pat.No. 5,322,055; U.S. Pat. No. 5,873,873; U.S. Pat. No. 5,980,510; U.S.Pat. No. 6,325,811; U.S. Pat. No. 6,773,444; U.S. Pat. No. 6,783,524;U.S. Pub. No. 2006/0079874; U.S. Pub. No. 2007/0191713; U.S. Pub. No.2007/0282333; U.S. Pub. No. 2008/0200940; U.S. Pub. No. 2009/0105750;U.S. Pub. No. 2010/0069940; U.S. Pub. No. 2011/0015660; U.S. Pub. No.2012/0112687; U.S. Pub. No. 2012/0116265; U.S. Pub. No. 2014/0005701;U.S. Pub. No. 2014/0114334; U.S. Pat. App. No. 61/410,603; and/or U.S.patent application Ser. No. 14/028,717. The disclosures of each of theforegoing patents, publications, and applications are incorporated byreference herein. As described therein and as will be described ingreater detail below, each instrument (10, 100) is operable to cuttissue and seal or weld tissue (e.g., a blood vessel, etc.)substantially simultaneously. It should also be understood thatinstruments (10, 100) may have various structural and functionalsimilarities with the HARMONIC ACE® Ultrasonic Shears, the HARMONICWAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears, and/orthe HARMONIC SYNERGY® Ultrasonic Blades. Furthermore, instruments (10,100) may have various structural and functional similarities with thedevices taught in any of the other references that are cited andincorporated by reference herein.

To the extent that there is some degree of overlap between the teachingsof the references cited herein, the HARMONIC ACE® Ultrasonic Shears, theHARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears,and/or the HARMONIC SYNERGY® Ultrasonic Blades, and the followingteachings relating to instruments (10, 100), there is no intent for anyof the description herein to be presumed as admitted prior art. Severalteachings herein will in fact go beyond the scope of the teachings ofthe references cited herein and the HARMONIC ACE® Ultrasonic Shears, theHARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears,and the HARMONIC SYNERGY® Ultrasonic Blades.

-   -   A. Exemplary Ultrasonic Surgical Instrument for Minimally        Invasive Surgical Procedures

FIG. 1 illustrates an exemplary ultrasonic surgical instrument (10) thatis configured to be used in minimally invasive surgical procedures(e.g., via a trocar or other small diameter access port, etc.).Instrument (10) of this example comprises a handle assembly (20), ashaft assembly (30), and an end effector (40). As shown in FIGS. 2-3B,shaft assembly (30) comprises an outer sheath (32), an inner tube (34)slidably disposed within outer sheath (32), and a waveguide (38)disposed within inner tube (34). As will be discussed in more detailbelow, longitudinal translation of inner tube (34) relative to outersheath (32) causes actuation of clamp arm (44) at end effector (40).Handle assembly (20) comprises a body (22) including a pistol grip (24)and a pair of buttons (26). Handle assembly (20) also includes a trigger(28) that is pivotable toward and away from pistol grip (24). It shouldbe understood, however, that various other suitable configurations maybe used, including but not limited to a scissor grip configuration. Inthe present example, a resilient member biases trigger (28) away frompistol grip (24). Trigger (28) is pivotable toward pistol grip (24) todrive inner tube (34) proximally relative to outer sheath (32). Whentrigger (28) is thereafter released or driven away from pistol grip(24), inner tube (34) is driven distally relative to outer sheath (32).By way of example only, trigger (28) may be coupled with inner tube (34)in accordance with the teachings of various references cited herein.Other suitable ways in which trigger (28) may be coupled with inner tube(34) will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

As shown in FIGS. 2-3B, end effector (40) includes an ultrasonic blade(42) and a pivoting clamp arm (44). Clamp arm (44) includes a clamp pad(46) facing ultrasonic blade (42). Clamp arm (44) is pivotably coupledwith a distal end of outer sheath (32) of shaft assembly (30), aboveultrasonic blade (42), via a pin (33). A distal end of inner tube (34)is pivotably coupled with a proximal end of clamp arm (44), belowultrasonic blade (42), via another pin (35). Thus, longitudinaltranslation of inner tube (34) relative to outer sheath (32) causesclamp arm (44) to pivot about pin (33) toward and away from ultrasonicblade (42) to thereby clamp tissue between clamp pad (46) and ultrasonicblade (42) to transect and/or seal the tissue. In particular, as seen inthe transition from FIG. 3A to FIG. 3B, proximal longitudinaltranslation of inner tube (34) relative to outer sheath (32) and handleassembly (20) causes clamp arm (44) to pivot toward ultrasonic blade(42); and distal longitudinal translation of inner tube (34) relative toouter sheath (32) and handle assembly (20) causes clamp arm (44) topivot away from ultrasonic blade (42). It should therefore be understoodthat pivoting of trigger (28) toward pistol grip (24) will cause clamparm (44) to pivot toward ultrasonic blade (42); and that pivoting oftrigger (28) away from pistol grip (24) will cause clamp arm (44) topivot away from ultrasonic blade (42).

An ultrasonic transducer assembly (12) extends proximally from body (22)of handle assembly (20). Transducer assembly (12) is coupled with agenerator (16) via a cable (14). Transducer assembly (12) receiveselectrical power from generator (16) and converts that power intoultrasonic vibrations through piezoelectric principles. Generator (16)may include a power source and control module that is configured toprovide a power profile to transducer assembly (12) that is particularlysuited for the generation of ultrasonic vibrations through transducerassembly (12). By way of example only, generator (16) may comprise a GEN300 sold by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. In additionor in the alternative, generator (16) may be constructed in accordancewith at least some of the teachings of U.S. Pub. No. 2011/0087212,entitled “Surgical Generator for Ultrasonic and ElectrosurgicalDevices,” published Apr 14, 2011, the disclosure of which isincorporated by reference herein. It should also be understood that atleast some of the functionality of generator (16) may be integrated intohandle assembly (20), and that handle assembly (20) may even include abattery or other on-board power source such that cable (14) is omitted.Still other suitable forms that generator (16) may take, as well asvarious features and operabilities that generator (16) may provide, willbe apparent to those of ordinary skill in the art in view of theteachings herein.

Ultrasonic vibrations that are generated by transducer assembly (12) arecommunicated along an acoustic waveguide (38), which extends throughshaft assembly (30) to reach ultrasonic blade (42). Waveguide (38) issecured within shaft assembly (30) via a pin (not shown), which passesthrough waveguide (38) and shaft assembly (30). This pin is located at aposition along the length of waveguide (38) corresponding to a nodeassociated with resonant ultrasonic vibrations communicated throughwaveguide (38). As noted above, when ultrasonic blade (42) is in anactivated state (i.e., vibrating ultrasonically), ultrasonic blade (42)is operable to effectively cut through and seal tissue, particularlywhen the tissue is being clamped between clamp pad (46) and ultrasonicblade (42). It should be understood that waveguide (38) may beconfigured to amplify mechanical vibrations transmitted throughwaveguide (38). Furthermore, waveguide (38) may include featuresoperable to control the gain of the longitudinal vibrations alongwaveguide (38) and/or features to tune waveguide (38) to the resonantfrequency of the system.

In the present example, the distal end of ultrasonic blade (42) islocated at a position corresponding to an anti-node associated withresonant ultrasonic vibrations communicated through waveguide (38), inorder to tune the acoustic assembly to a preferred resonant frequencyf_(o) when the acoustic assembly is not loaded by tissue. Whentransducer assembly (12) is energized, the distal end of ultrasonicblade (42) is configured to move longitudinally in the range of, forexample, approximately 10 to 500 microns peak-to-peak, and in someinstances in the range of about 20 to about 200 microns at apredetermined vibratory frequency f_(o) of, for example, 55.5 kHz. Whentransducer assembly (12) of the present example is activated, thesemechanical oscillations are transmitted through the waveguide to reachultrasonic blade (102), thereby providing oscillation of ultrasonicblade (102) at the resonant ultrasonic frequency. Thus, when tissue issecured between ultrasonic blade (42) and clamp pad (46), the ultrasonicoscillation of ultrasonic blade (42) may simultaneously sever the tissueand denature the proteins in adjacent tissue cells, thereby providing acoagulative effect with relatively little thermal spread. In someversions, an electrical current may also be provided through ultrasonicblade (42) and/or clamp pad (46) to also seal the tissue.

An operator may activate buttons (26) to selectively activate transducerassembly (12) to thereby activate ultrasonic blade (42). In the presentexample, two buttons (26) are provided—one for activating ultrasonicblade (42) at a low power and another for activating ultrasonic blade(42) at a high power. However, it should be understood that any othersuitable number of buttons and/or otherwise selectable power levels maybe provided. For instance, a foot pedal may be provided to selectivelyactivate transducer assembly (12). Buttons (26) of the present exampleare positioned such that an operator may readily fully operateinstrument (10) with a single hand. For instance, the operator mayposition their thumb about pistol grip (24), position their middle,ring, and/or little finger about trigger (28), and manipulate buttons(26) using their index finger. Of course, any other suitable techniquesmay be used to grip and operate instrument (10); and buttons (26) may belocated at any other suitable positions.

The foregoing components and operabilities of instrument (10) are merelyillustrative. Instrument (10) may be configured in numerous other waysas will be apparent to those of ordinary skill in the art in view of theteachings herein. By way of example only, at least part of instrument(10) may be constructed and/or operable in accordance with at least someof the teachings of any of the following, the disclosures of which areall incorporated by reference herein: U.S. Pat. No. 5,322,055; U.S. Pat.No. 5,873,873; U.S. Pat. No. 5,980,510; U.S. Pat. No. 6,325,811; U.S.Pat. No. 6,783,524; U.S. Pub. No. 2006/0079874; U.S. Pub. No.2007/0191713; U.S. Pub. No. 2007/0282333; U.S. Pub. No. 2008/0200940;U.S. Pub. No. 2010/0069940; U.S. Pub. No. 2011/0015660; U.S. Pub. No.2012/0112687; U.S. Pub. No. 2012/0116265; U.S. Pub. No. 2014/0005701;and/or U.S. Pub. No. 2014/0114334. Additional merely illustrativevariations for instrument (10) will be described in greater detailbelow. It should be understood that the below described variations maybe readily applied to instrument (10) described above and any of theinstruments referred to in any of the references that are cited herein,among others.

-   -   B. Exemplary Ultrasonic Surgical Instrument for Open Surgical        Procedures

FIG. 4 illustrates an exemplary ultrasonic surgical instrument (100)that is configured to be used in open surgical procedures. Instrument(100) of this example comprises a handle assembly (120), a shaftassembly (130), and an end effector (140). Handle assembly (120)comprises a body (122) including a finger grip ring (124) and a pair ofbuttons (126). Instrument (100) also includes a clamp arm assembly (150)that is pivotable toward and away from body (122). Clamp arm (150)includes a shank (152) with a thumb grip ring (154). Thumb grip ring(154) and finger grip ring (124) together provide a scissor grip type ofconfiguration. It should be understood, however, that various othersuitable configurations may be used, including but not limited to apistol grip configuration.

Shaft assembly (130) comprises an outer sheath (132) extending distallyfrom body (122). A cap (134) is secured to the distal end of sheath(132). As best seen in FIGS. 5-6B, end effector (140) comprises anultrasonic blade (142) and a clamp arm (144). Ultrasonic blade (142)extends distally from cap (134). Clamp arm (144) is an integral featureof clamp arm assembly (150). Clamp arm (144) includes a clamp pad (146)facing ultrasonic blade (142). Clamp arm assembly (150) is pivotallycoupled with outer sheath (132) via a pin (156). Clamp arm (144) ispositioned distal to pin (156); while shank (152) and thumb grip ring(154) are positioned proximal to pin (156). Thus, as shown in FIGS.6A-6B, clamp arm (144) is pivotable toward and away from ultrasonicblade (142) based on pivoting of thumb grip ring (154) toward and awayfrom body (122) of handle assembly (120). It should therefore beunderstood that an operator may squeeze thumb grip ring (154) towardbody (122) to thereby clamp tissue between clamp pad (146) andultrasonic blade (142) to transect and/or seal the tissue. In someversions, one or more resilient members are used to bias clamp arm (144)to the open position shown in FIG. 6A. By way of example only, such aresilient member may comprise a leaf spring, a torsion spring, and/orany other suitable kind of resilient member.

Referring back to FIG. 4, an ultrasonic transducer assembly (112)extends proximally from body (122) of handle assembly (120). Transducerassembly (112) is coupled with a generator (116) via a cable (114).Transducer assembly (112) receives electrical power from generator (116)and converts that power into ultrasonic vibrations through piezoelectricprinciples. Generator (116) may include a power source and controlmodule that is configured to provide a power profile to transducerassembly (112) that is particularly suited for the generation ofultrasonic vibrations through transducer assembly (112). By way ofexample only, generator (116) may comprise a GEN 300 sold by EthiconEndo-Surgery, Inc. of Cincinnati, Ohio. In addition or in thealternative, generator (116) may be constructed in accordance with atleast some of the teachings of U.S. Pub. No. 2011/0087212, entitled“Surgical Generator for Ultrasonic and Electrosurgical Devices,”published Apr. 14, 2011, the disclosure of which is incorporated byreference herein. It should also be understood that at least some of thefunctionality of generator (116) may be integrated into handle assembly(120), and that handle assembly (120) may even include a battery orother on-board power source such that cable (114) is omitted. Stillother suitable forms that generator (116) may take, as well as variousfeatures and operabilities that generator (116) may provide, will beapparent to those of ordinary skill in the art in view of the teachingsherein.

Ultrasonic vibrations that are generated by transducer assembly (112)are communicated along an acoustic waveguide (138), which extendsthrough shaft assembly (130) to reach ultrasonic blade (142). Waveguide(138) is secured within shaft assembly (130) via a pin (not shown),which passes through waveguide (138) and shaft assembly (130). This pinis located at a position along the length of waveguide (138)corresponding to a node associated with resonant ultrasonic vibrationscommunicated through waveguide (138). As noted above, when ultrasonicblade (142) is in an activated state (i.e., vibrating ultrasonically),ultrasonic blade (142) is operable to effectively cut through and sealtissue, particularly when the tissue is being clamped between clamp pad(146) and ultrasonic blade (142). It should be understood that waveguide(138) may be configured to amplify mechanical vibrations transmittedthrough waveguide (138). Furthermore, waveguide (138) may includefeatures operable to control the gain of the longitudinal vibrationsalong waveguide (138) and/or features to tune waveguide (138) to theresonant frequency of the system.

In the present example, the distal end of ultrasonic blade (142) islocated at a position corresponding to an anti-node associated withresonant ultrasonic vibrations communicated through waveguide (138), inorder to tune the acoustic assembly to a preferred resonant frequencyf_(o) when the acoustic assembly is not loaded by tissue. Whentransducer assembly (112) is energized, the distal end of ultrasonicblade (142) is configured to move longitudinally in the range of, forexample, approximately 10 to 500 microns peak-to-peak, and in someinstances in the range of about 20 to about 200 microns at apredetermined vibratory frequency f_(o) of, for example, 55.5 kHz. Whentransducer assembly (112) of the present example is activated, thesemechanical oscillations are transmitted through the waveguide to reachultrasonic blade (102), thereby providing oscillation of ultrasonicblade (102) at the resonant ultrasonic frequency. Thus, when tissue issecured between ultrasonic blade (142) and clamp pad (46), theultrasonic oscillation of ultrasonic blade (142) may simultaneouslysever the tissue and denature the proteins in adjacent tissue cells,thereby providing a coagulative effect with relatively little thermalspread. In some versions, an electrical current may also be providedthrough ultrasonic blade (142) and/or clamp pad (146) to also seal thetissue.

An operator may activate buttons (126) to selectively activatetransducer assembly (112) to thereby activate ultrasonic blade (142). Inthe present example, two buttons (126) are provided—one for activatingultrasonic blade (142) at a low power and another for activatingultrasonic blade (142) at a high power. However, it should be understoodthat any other suitable number of buttons and/or otherwise selectablepower levels may be provided. For instance, a foot pedal may be providedto selectively activate transducer assembly (112). Buttons (126) of thepresent example are positioned such that an operator may readily fullyoperate instrument (100) with a single hand. For instance, the operatormay position their thumb in thumb grip ring (154), position their ringfinger in finger grip ring (124), position their middle finger aboutbody (122), and manipulate buttons (126) using their index finger. Ofcourse, any other suitable techniques may be used to grip and operateinstrument (100); and buttons (126) may be located at any other suitablepositions.

The foregoing components and operabilities of instrument (100) aremerely illustrative. Instrument (100) may be configured in numerousother ways as will be apparent to those of ordinary skill in the art inview of the teachings herein. By way of example only, at least part ofinstrument (100) may be constructed and/or operable in accordance withat least some of the teachings of any of the following, the disclosuresof which are all incorporated by reference herein: U.S. Pat. No.5,322,055; U.S. Pat. No. 5,873,873; U.S. Pat. No. 5,980,510; U.S. Pat.No. 6,325,811; U.S. Pat. No. 6,783,524; U.S. Pub. No. 2006/0079874; U.S.Pub. No. 2007/0191713; U.S. Pub. No. 2007/0282333; U.S. Pub. No.2008/0200940; U.S. Pub. No. 2010/0069940; U.S. Pub. No. 2011/0015660;U.S. Pub. No. 2012/0112687; U.S. Pub. No. 2012/0116265; U.S. Pub. No.2014/0005701; U.S. Pub. No. 2014/0114334; and/or U.S. patent applicationSer. No. 14/031,665. Additional merely illustrative variations forinstrument (100) will be described in greater detail below. It should beunderstood that the below described variations may be readily applied toinstrument (100) described above and any of the instruments referred toin any of the references that are cited herein, among others.

II. Exemplary Features for Providing Heat Management in an UltrasonicSurgical Instrument

In some instances, one or more regions of instrument (10, 100) may heatup during extended operation of instrument (10, 100) in a surgicalprocedure. By way of example only, blade (42, 142), clamp arm (44, 144),and/or other portions of instrument (10, 100) may eventually heat upover time. Such heating may be caused by friction and/or other factors.To the extent that the heat is initially generated in one particularcomponent of instrument (10, 100) (e.g., blade (42, 142) or clamp arm(44, 144), etc.), such heat may be gradually transmitted to otherportions of instrument (10, 100). It may be desirable to minimize suchheating and/or otherwise manage such heating in order to avoid havingheated portions of instrument (10, 100) contact tissue that should notbe heated. For instance, the operator may wish for end effector (40,140) to be relatively cool when the operator wishes to use end effector(40, 140) to perform spreading blunt dissections and/or simple tissuegrasping, etc. It may also be desirable to minimize heat and/orotherwise manage heat in a way that does not significantly increase thesize or operability of instrument (10, 100). Several examples of howheating may be minimized and/or otherwise managed are described ingreater detail below; while other examples will be apparent to those ofordinary skill in the art in view of the teachings herein.

In addition to the examples described below, it should be understoodthat one or more portions of instrument (10, 100) may include a thermalinsulator or barrier coating (e.g., a thin coating of thermal insulatoror barrier material with a very low thermal conductivity). An example ofa thermal insulator or barrier coating is a nanocomposite (e.g.,hydro-NM-oxide) in an acrylic resin suspension. An example of such acoating is NANSULATE® coating by Industrial Nanotech, Inc. of Naples,Florida. Additional merely illustrative examples of thermal insulator orbarrier coatings include the following: EST 1711 by Ellison SurfaceTechnologies, Inc. of Mason, Ohio; EST 1732 by Ellison SurfaceTechnologies, Inc. of Mason, Ohio; EST 3030 by Ellison SurfaceTechnologies, Inc. of Mason, Ohio; EST 1711+EST 3030 by Ellison SurfaceTechnologies, Inc. of Mason, Ohio; Oxytech V by Techmetals, Inc. ofDayton, Ohio; Alumina Titania; Zirconium Oxide; Aluminum Oxide; and/orvarious other kinds of coatings, including combinations thereof.

A thermal insulator or barrier coating may be applied to variousexternal surfaces of instrument (10, 100), such as regions of blade (42,142) that are not intended to contact tissue, clamp arm (44, 144), clamppad (46, 146), outer sheath (32, 132), cap (134), etc. In addition or inthe alternative, such a coating may be applied to various internalsurfaces of instrument (10, 100), such as surfaces in generator (16,116), transducer assembly (12, 112), internal electronics components,etc. In addition to providing a thermal barrier or insulation, such acoating may serve as a corrosion barrier, fire block, etc. In the belowexamples that include various components that are added to or otherwiseincorporated into variations of instrument (10, 100), the coating mayalso be applied to one or more regions of such components. Othersuitable ways in which a thermal coating may be incorporated intoinstrument (10, 100) and variations thereof will be apparent to those ofordinary skill in the art in view of the teachings herein.

To the extent that any of the examples discussed below are shown anddescribed in the context of a variation of one particular kind ofinstrument (10 or 100), it should be understood that the same teachingsmay be readily applied to the other kind of instrument (10 or 100). Eachexample described below should therefore not be viewed as only havingapplicability to either instrument (10) or instrument (100).Furthermore, it is contemplated that the teachings below may be readilyapplied to other kinds of instruments, not just variations ofinstruments (10, 100).

As will be described in greater detail below, one or more shieldingfeatures may be used to avoid direct contact between a hot portion ofinstrument (10, 100) and tissue (or other structures). A gap may bedefined between the shielding feature and the corresponding hot portionof instrument (10, 100), to avoid or minimize communication of heat fromthe hot portion of instrument (10, 100) and the shielding feature. Sucha gap may be filled with liquid, air or some other gas, a solidinsulating material, and/or any other suitable kind of filler, includingcombinations thereof. It should also be understood that various kinds ofstructural features may be interposed between the hot portion ofinstrument (10, 100) and the shielding feature, including but notlimited to a roughened surface, grooves, dimples, pimples, nubs,knurling, a honeycomb structure, etc. Such structural features mayminimize transfer of heat from the hot portion of instrument (10, 100)and the shielding feature. Similarly, a shielding feature (and/or a hotfeature of instrument (10, 100)) may include external surface structuressuch as a roughened surface, grooves, dimples, pimples, nubs, knurling,a honeycomb structure, etc., to minimize transfer of heat from theshielding feature (or hot feature) to adjacent tissue, etc. Variousmerely illustrative examples of shielding features will be described ingreater detail below. Other suitable examples will be apparent to thoseof ordinary skill in the art in view of the teachings herein.

It should be understood that any of the shields described below maycomprise a temperature sensitive material. For instance, such atemperature sensitive material may be configured to change color and/orotherwise change in appearance in response to changes in temperature. Insome such examples, the shield may change color as the temperature ofthe blade (42, 142) that is adjacent to the shield increases. The shieldmay thus provide the operator with a visual indication of the thermalcondition of blade (42, 142) and/or the rest of end effector (40, 140).Various suitable materials that may be used to provide such propertieswill be apparent to those of ordinary skill in the art in view of theteachings herein. By way of example only, such material may includeHuntsman RenShape 7820.

In some versions, one or more of the shields described below comprisesPolybenzimidazole-Polyetherketoneketone (PBI-PEKK). As another merelyillustrative example, one or more of the shields described below maycomprise Perfluoroalkoxy (PFA). In addition or in the alternative, anyof the shields described herein may comprise glass-filled PFA;Polyamide-imide (PAI), such as TORLON; Thermoplastic Polyimide (TPI),such as EXTEM; Polyetherimide (PEI), such as ULTEM; carbon-filled PEI;Polyetheretherketone (PEEK); glass-filled Polyaryletherketone (PAEK);DSM Somos ProtoTherm 12120; and/or DSM Somos NanoTool. Still othersuitable materials that may be used to form the shields described belowwill be apparent to those of ordinary skill in the art in view of theteachings herein. Similarly, various suitable methods for formingshields (e.g., injection molding, SLA, etc.) will be apparent to thoseof ordinary skill in the art in view of the teachings herein.

-   -   A. Exemplary Longitudinally Translating Blade Shield

FIGS. 7A-8 show the distal portion of an exemplary instrument (500) thatincludes a translating heat shield (560). Instrument (500) of thisexample is substantially similar to instrument (100) described above. Inparticular, instrument (500) of this example includes a shaft assembly(530), a clamp arm assembly (550), an ultrasonic blade (542), and awaveguide (538). Shaft assembly (530) includes an outer sheath (32) andheat shield (560). Clamp arm assembly (550) includes a shank (552) and aclamp arm (544) with a clamp pad (546). Clamp arm assembly (550) ispivotally coupled with outer sheath (532) via a pin (556). Thus, asshown in FIGS. 7A-7B, clamp arm (544) is pivotable toward and away fromultrasonic blade (542) based on pivoting of shank (552) toward and awayfrom shaft assembly (530). It should be understood that grippingfeatures similar to rings (124, 154) may be provided to facilitatepivotal movement of shank (552) relative to shaft assembly (530).

Instrument (500) of this example further includes a pivoting link (570).One end of pivoting link (570) is pivotally coupled with shank (552) viaa pin (572), which is located generally proximally relative to pin(556). The other end of pivoting link (570) is pivotally coupled withheat shield (560) via a pin (574). It should be understood that pivotinglink (570) is operable to drive heat shield (560) distally when shank(552) is pivoted away from shaft assembly (530), as shown in FIG. 7B;and retract shield (560) proximally when shank (552) is pivoted towardshaft assembly (530), as shown in FIG. 7A. As best seen in FIG. 8, heatshield (560) is configured to define a gap (580) between the innersurface of heat shield (560) and the outer surface of ultrasonic blade(542). This gap (580) prevents heat from being transferred fromultrasonic blade (542) to heat shield (560). Heat shield (560) thusremains substantially cool during operation of instrument (500), even ifultrasonic blade (542) heats up. By covering a portion of ultrasonicblade (542) when end effector (540) is in the open configuration asshown in FIG. 7B, heat shield (560) also substantially prevents tissuefrom directly contacting a substantial portion of ultrasonic blade(542).

In the present example, heat shield (560) just covers a portion ofultrasonic blade (542). It should be understood that heat shield (560)may be configured to cover more or less of ultrasonic blade (542) thanis shown as being covered in FIG. 7B. It should also be understood thatwaveguide (538), blade (542), sheath (532), and/or some other portion ofinstrument (500) may include one or more rails and/or other structuralfeatures that provide support and guidance for heat shield (560) as heatshield (560) travels between proximal and distal positions. Suchsupport/guidance structures may substantially maintain sizing and/orspacing in gap (580). Moreover, while air is positioned in gap (580) inthe present example, it should be understood that any suitable substanceor material may be positioned in gap (580). By way of example only, anabsorbent pad that is saturated with a cooling fluid may be positionedin gap (580) to assist in cooling of ultrasonic blade (542) inaccordance with the teachings herein. In addition or in the alternative,a wiping structure may be provided in gap (580) to assist in driving anysurgical debris (e.g., coagulated blood, etc.) from the surface ofultrasonic blade (542). In some variations, shaft assembly (530)includes a collet feature that is coaxially positioned between heatshield (560) and blade (542). In some such versions, the collet featureis resiliently biased to assume an expanded configuration where thecollet feature does not contact blade (542). When heat shield (560) isdriven distally, heat shield engages a tapered portion of the collet anddeforms the collet inwardly into engagement with blade (542). While thecollet is in contact with the blade, the collet serves as a heat sinkand thus draws heat away from blade (542). This drawn heat may befurther transferred to shaft assembly (530). Still other suitablevariations will be apparent to those of ordinary skill in the art inview of the teachings herein.

-   -   B. Exemplary Laterally Deflecting Blade Shield

FIGS. 9A-9B show an exemplary alternative end effector (640) that may beused in place of end effector (40). End effector (640) of this exampleis substantially similar to end effector (40) described above. Inparticular, end effector (640) includes an ultrasonic blade (642) and apivoting clamp arm (644) with clamp pad (646). Shaft assembly (630) issubstantially similar to shaft assembly (30) described above. Inparticular, shaft assembly (630) includes an outer sheath (632) and aninner tube (634). Clamp arm (644) is pivotally coupled with outer sheath(632) and with inner tube (634), such that clamp arm (644) pivots toward(FIG. 9B) and away from (FIG. 9A) blade (642) in response to translationof inner tube (634) relative to outer sheath (632).

End effector (640) of this example further includes a blade shield(660). The proximal end of blade shield (660) is secured to inner tube(634). Shield (660) is contoured to bend around a knuckle (648) of clamparm (644) and complement the curvature of blade (642) when end effector(640) is in an open configuration as shown in FIG. 9A. In some versions,shield (660) contacts blade (642) when end effector (640) is in an openconfiguration as shown in FIG. 9A. When end effector (640) transitionsto the closed configuration, knuckle (648) drives shield (660) outwardlyaway from blade (642) as shown in FIG. 9B. In the present example,shield (660) comprises a resilient material (e.g., metal, etc.), suchthat shield (660) returns back toward blade (642) when end effector(640) returns to the open configuration. Those of ordinary skill in theart will immediately recognize upon viewing FIGS. 9A-9B that clamp arm(644) travels along a first plane as clamp arm (644) moves toward andaway from blade (642); while shield (660) travels along a second planeas shield (660) moves toward and away from blade (642), with the secondplane being transverse to the first plane. Alternatively, theserespective planes of travel may have any other suitable relationship.

FIG. 10 shows yet an exemplary variation where an end effector (670)that is otherwise identical to end effector (640) includes a pair ofshields (680, 682). Shields (680, 682) of this example are substantiallysimilar to shield (660) except that shields (680, 682) of this exampleare on opposite lateral sides of blade (672) and wrap completely aroundblade (672). Shields (680, 682) meet at a seam (684) positioned distalto blade (672) when end effector (670) is in an open configuration.Shields (680 682) may deflect outwardly away from blade (672), spreadingapart from each other, when end effector (670) is closed. In the presentexamples, shields (660, 680, 682) serve as a shield that prevents directcontact between tissue and at least a portion of blade (642). Inaddition or in the alternative, shields (660, 680, 682) may serve as aheat sink that draws heat away from blade (642, 672). It should also beunderstood that shields (660, 680, 682) may include an absorbent padthat is saturated with a cooling fluid. Such a pad may contact blade(642, 672) when end effector (640, 670) is in the open configuration andthereby cool blade (642, 672) in accordance with the teachings above. Asyet another merely illustrative variation, shield (660, 680, 682) mayinclude silicon tubing extending along at least a portion of the lengthof shield (660, 680, 682). As will be described in greater detail below,such silicon tubing may capture vapor plumes emitted duringcutting/sealing of tissue by blade (642, 672) and/or other fluid from asurgical site. Such captured vapor plumes and/or other fluid from asurgical site may assist in cooling of shield (660, 680, 682) and/orblade (642). Other suitable variations will be apparent to those ofordinary skill in the art in view of the teachings herein.

-   -   C. Exemplary Stationary Blade Shield

FIGS. 11-13 depict an exemplary blade shield (700), which is fitted on ablade (742) of an end effector (740). End effector (740) of this exampleis substantially similar to end effector (40) described above. Shield(700) of the present example is formed of a thermally insulativematerial. By way of example only, shield (700) may comprise silicone,graphine, graphite, and/or any other suitable material(s). End effector(740) of this example is substantially similar to end effector (40)described above. In particular, end effector (740) includes anultrasonic blade (742) and a pivoting clamp arm (744) with clamp pad(746). Shaft assembly (730) is substantially similar to shaft assembly(30) described above. In particular, shaft assembly (730) includes anouter sheath (732) and an inner tube (734). Clamp arm (744) is pivotallycoupled with outer sheath (732) and with inner tube (734), such thatclamp arm (744) pivots toward and away from blade (742) in response totranslation of inner tube (734) relative to outer sheath (732). In thepresent example, the proximal end of shield (700) is compressed betweenthe proximal end of blade (742) and the distal end of inner tube (734),such that shield (700) is held in place by pressure/friction.Alternatively, shield (700) may be secured by a bushing, by necking ofinner tube (734), by crimping inner tube (734), by an adhesive, and/orusing any other suitable structures/techniques as will be apparent tothose of ordinary skill in the art in view of the teachings herein.

As shown, shield (700) of this example is fitted snugly about blade(742), covering the distal tip (702) of blade (742). However, shield(700) includes an opening (704) that leaves a clamping region (706) ofblade (742) exposed. Thus, as clamp arm (744) is pivoted toward blade(742), blade (742) still cuts and seals tissue that is compressedbetween clamp pad (746) and clamping region (706) of blade (742) justlike blade (42) described above. However, shield (700) prevents the restof blade (742) from coming into direct contact with tissue. Shield (700)may thus prevent blade (742) from inadvertently damaging tissue whenblade (742) gets hot during extended use of end effector (740). In somevariations, a gap is defined between shield (700) and blade (742). Sucha gap may receive vapor and/or fluid from the surgical site. Such vaporand/or fluid may assist in cooling blade (742). While shield (700) ofthe present example covers distal tip (702) of blade (742) it should beunderstood that shield (700) may instead distally terminate at any othersuitable location in relation to distal tip (702). For instance, shield(700) may distally terminate at the longitudinal mid-region of blade(742), anywhere proximal to the longitudinal mid-region of blade (742),or anywhere distal to the longitudinal mid-region of blade (742). Asanother merely illustrative variation, shield (700) may be selectivelyretractable to selectively expose a distal region of blade (742) or eventhe full length of blade (742). Various suitable ways in which shield(700) may be selectively retracted and advanced will be apparent tothose of ordinary skill in the art in view of the teachings herein.

FIGS. 14-16 depict another exemplary blade shield (800), which is fittedon a blade (842) of an end effector (840). Shield (800) of the presentexample is formed of a thermally insulative material. By way of exampleonly, shield (800) may comprise silicone, graphine, graphite, and/or anyother suitable material(s). End effector (840) of this example issubstantially similar to end effector (140) described above. Inparticular, end effector (840) includes an ultrasonic blade (842) and apivoting clamp arm (844) with clamp pad (846). Shaft assembly (830) issubstantially similar to shaft assembly (130) described above. Inparticular, shaft assembly (830) includes an outer sheath (832) and acap (834). Clamp arm (844) is integral with a shank (852), thecombination of which is pivotally coupled with outer sheath (832) suchthat clamp arm (844) pivots toward and away from blade (842) in responseto pivoting of shank (852) relative to shaft assembly (830). Shield(800) may be held in place similar to shield (700) as described above;and/or using any other suitable structures/techniques as will beapparent to those of ordinary skill in the art in view of the teachingsherein.

As shown, shield (800) of this example is fitted snugly about blade(842), covering the distal tip (802) of blade (842). However, shield(800) includes an opening (804) that leaves a clamping region (806) ofblade (842) exposed. Thus, as clamp arm (844) is pivoted toward blade(842), blade (842) still cuts and seals tissue that is compressedbetween clamp pad (846) and clamping region (806) of blade (842) justlike blade (42) described above. However, shield (800) prevents the restof blade (842) from coming into direct contact with tissue. Shield (800)may thus prevent blade (842) from inadvertently damaging tissue whenblade (842) gets hot during extended use of end effector (840). In somevariations, a gap is defined between shield (800) and blade (842). Sucha gap may receive vapor and/or fluid from the surgical site. Such vaporand/or fluid may assist in cooling blade (842). While shield (800) ofthe present example covers distal tip (802) of blade (842) it should beunderstood that shield (800) may instead distally terminate at any othersuitable location in relation to distal tip (802). For instance, shield(800) may distally terminate at the longitudinal mid-region of blade(842), anywhere proximal to the longitudinal mid-region of blade (842),or anywhere distal to the longitudinal mid-region of blade (842). Asanother merely illustrative variation, shield (800) may be selectivelyretractable to selectively expose a distal region of blade (842) or eventhe full length of blade (842). Various suitable ways in which shield(800) may be selectively retracted and advanced will be apparent tothose of ordinary skill in the art in view of the teachings herein.

FIG. 17 depicts another exemplary blade shield (900), which is fitted ona blade (942) of an end effector (940). Shield (900) of the presentexample is formed of a thermally insulative material. By way of exampleonly, shield (900) may comprise silicone, graphine, graphite, and/or anyother suitable material(s). End effector (940) of this example issubstantially similar to end effector (40) described above. Inparticular, end effector (940) includes an ultrasonic blade (942) and apivoting clamp arm (944) with clamp pad (946). Shaft assembly (930) issubstantially similar to shaft assembly (30) described above. Inparticular, shaft assembly (930) includes an outer sheath (932) and aninner tube (934). Clamp arm (944) is pivotally coupled with outer sheath(932) and with inner tube (934), such that clamp arm (944) pivots towardand away from blade (942) in response to translation of inner tube (934)relative to outer sheath (932). Shield (900) may be held in placesimilar to shield (700) as described above; and/or using any othersuitable structures/techniques as will be apparent to those of ordinaryskill in the art in view of the teachings herein.

As shown, shield (900) of this example is fitted snugly about blade(942), covering the distal tip (902) of blade (942). However, shield(900) includes an opening (904) that leaves a clamping region (906) ofblade (942) exposed. Thus, as clamp arm (944) is pivoted toward blade(942), blade (942) still cuts and seals tissue that is compressedbetween clamp pad (946) and clamping region (906) of blade (942) justlike blade (42) described above. However, shield (900) prevents the restof blade (942) from coming into direct contact with tissue. Shield (900)may thus prevent blade (942) from inadvertently damaging tissue whenblade (942) gets hot during extended use of end effector (940). In somevariations, a gap is defined between shield (900) and blade (942). Sucha gap may receive vapor and/or fluid from the surgical site. Such vaporand/or fluid may assist in cooling blade (942). While shield (900) ofthe present example covers distal tip (902) of blade (942) it should beunderstood that shield (900) may instead distally terminate at any othersuitable location in relation to distal tip (902). For instance, shield(900) may distally terminate at the longitudinal mid-region of blade(942), anywhere proximal to the longitudinal mid-region of blade (942),or anywhere distal to the longitudinal mid-region of blade (942). Asanother merely illustrative variation, shield (900) may be selectivelyretractable to selectively expose a distal region of blade (942) or eventhe full length of blade (942). Various suitable ways in which shield(900) may be selectively retracted and advanced will be apparent tothose of ordinary skill in the art in view of the teachings herein.

Unlike shield (700) described above, shield (900) of the present exampleincludes a series of teeth (905) adjacent to opening (904). Teeth (905)are configured to assist in gripping of tissue. In the present example,teeth (905) extend past the top plane of clamping region (906) of blade(942), such that teeth (905) will engage tissue clamped between clamppad (946) and blade (942) before blade (942) engages the tissue. Thematerial forming teeth (905) is soft enough to not pierce or tear thetissue, such that teeth (905) merely provide an enhanced grip on thetissue by end effector (940). Other suitable ways in which a shield mayincorporate teeth will be apparent to those of ordinary skill in the artin view of the teachings herein.

FIGS. 18-20 show another merely illustrative shield (1000) coupled withan ultrasonic blade (1042). It should be understood that shield (1000)and blade (1042) may be readily incorporated into end effector (40)described above. Shield (1000) of the present example is formed of athermally insulative material. By way of example only, shield (1000) maycomprise silicone, graphine, graphite, and/or any other suitablematerial(s). Shield (1000) may be held in place similar to shield (700)as described above; and/or using any other suitablestructures/techniques as will be apparent to those of ordinary skill inthe art in view of the teachings herein.

Unlike shield (700) described above, shield (1000) of this exampleterminates proximal to the distal tip (1043) of blade (1042). Inparticular, shield (1000) includes a distal terminal end (1002) that ispositioned near the longitudinal mid-region of blade (1042). In somevariations, distal terminal end (1002) is positioned somewhere proximalto the longitudinal mid-region of blade (1042); or somewhere distal tothe longitudinal mid-region of blade (1042). As another merelyillustrative variation, shield (1000) may be selectively retractable toselectively expose a distal region of blade (1042) or even the fulllength of blade (1042). Various suitable ways in which shield (1000) maybe selectively retracted and advanced will be apparent to those ofordinary skill in the art in view of the teachings herein. It should beunderstood that, by exposing the distal region of blade (1042), shieldof the present example use of enables blade (1042) to performback-cutting operations, spot coagulation, etc. and/or other operationsthat might not otherwise be possible in versions where the distal regionof blade (1042) is covered.

Also unlike shield (700), shield (1000) of the present example extendsaround the full circumferential perimeter of the profile of blade(1042), as best seen in FIG. 19. In other words, shield (1000) lacks apreformed opening like opening (704). However, after a clamp arm (e.g.,similar to clamp arms (44, 744, etc.)) clamps tissue against thecombination of blade (1042) and shield (1000) while blade (1042) isultrasonically activated, the action against shield (1000) mayeventually rupture shield as shown in FIG. 20. In particular, suchrupturing may define an opening (1004) that is similar to opening (704),exposing a tissue clamping region (1045) of blade (1042). It should beunderstood that a clamp arm would be clamping toward tissue clampingregion (1045) in this example.

FIGS. 21A-21B depict a merely illustrative variation of shield (1000).In particular FIGS. 21A-21B show a shield (1100) that has a preformedslit (1104). Slit (1104) is positioned adjacent to a tissue clampingregion (1145) of a blade (1142). Shield (1100) of the present example isformed of a thermally insulative material. By way of example only,shield (1100) may comprise silicone, graphine, graphite, and/or anyother suitable material(s). Shield (1100) of this example may alsoterminate proximal to the distal tip of blade (1142) (e.g., near thelongitudinal mid-region of blade (1142), somewhere proximal to thelongitudinal mid-region of blade (1142), or somewhere distal to thelongitudinal mid-region of blade (1142)). Shield (1100) may also beselectively retractable relative to blade (1142).

As shown in FIG. 21A, shield (1100) fits closely about blade (1142) whena clamp arm (1144) is positioned away from blade (1142). However, whenclamp arm (1144) is pivoted into engagement with blade (1142), shield(1000) deforms at slit (1104) and slides transversely along blade(1142), allowing clamp arm (1144) to contact tissue clamping region(1145) of a blade (1142) as shown in FIG. 21B. In particular, the edgesof shield (1100) near slit (1104) spread outwardly to allow shield(1000) to slide transversely relative to blade (1142). During use ofblade (1142) and shield (1100), tissue may be interposed between clamparm (1144) and blade (1142), though it should be understood that shield(1100) may nevertheless still react as shown in FIG. 21B. In the presentexample, clamp arm (1144) and/or tissue that is interposed between clamparm (1144) and blade (1142) cause the deformation of shield (1100). Insome other versions, one or more features (e.g., camming surfaces,ridges, pegs, etc.) in one or more components such as outer sheath (32)and/or inner tube (34) cause the deformation of shield (1100). Othersuitable ways in which shield (1100) may be deformed to expose tissueclamping region (1145) of blade (1142) will be apparent to those ofordinary skill in the art in view of the teachings herein.

As also shown in FIG. 21B, a gap (1110) is defined between the interiorof shield (1100) and the exterior of blade (1142) when shield (1100)slides transversely from blade (1142) during deformation of shield(1100) at slit (1104). This gap (1110) may capture vapor plumes emittedduring cutting/sealing of tissue by blade (1142) and/or other fluid froma surgical site. Such captured vapor plumes and/or other fluid from asurgical site may assist in cooling of shield (1100) and/or blade(1142). In addition or in the alternative, gap (1110) may provide a pathfor communicating a cooling fluid (e.g., from a fluid source locatedproximal to shield (1100) and blade (1142), etc.). Such a cooling fluidmay be used to further assist in cooling of shield (1100) and/or blade(1142). In some versions, when clamp arm (1144) is pivoted back awayfrom blade (1142), shield (1100) substantially returns to theconfiguration shown in FIG. 21A, such that gap (1110) shrinks orsubstantially disappears. Those of ordinary skill in the art willimmediately recognize upon viewing FIGS. 21A-21B that clamp arm (1144)travels along a first plane as clamp arm (1144) moves toward and awayfrom blade (1142); while shield (1100) also travels along the same firstplane as shield (1100) moves toward and away from blade (1142).Alternatively, these respective planes of travel may have any othersuitable relationship. It should also be understood upon viewing FIGS.21A-21B that movement of clamp arm (1144) drives the movement of shield(1100) in this example. Other suitable ways in which movement of a clamparm may drive movement of a shield will be apparent to those of ordinaryskill in the art in view of the teachings herein.

FIG. 22 shows a merely illustrative variation of shield (1100). Inparticular FIG. 22 shows a shield (1200) that has a preformed slit(1204) positioned adjacent to a tissue clamping region (1245) of a blade(1242). Shield (1200) of the present example is formed of a thermallyinsulative material. By way of example only, shield (1200) may comprisesilicone, graphine, graphite, and/or any other suitable material(s).Shield (1200) of this example may also terminate proximal to the distaltip of blade (1242) (e.g., near the longitudinal mid-region of blade(1242), somewhere proximal to the longitudinal mid-region of blade(1242), or somewhere distal to the longitudinal mid-region of blade(1242)). Shield (1200) may also be selectively retractable relative toblade (1242). Unlike shield (1100), shield (1200) of this example doesnot fit closely about blade (1242) when a clamp arm is positioned awayfrom blade (1242). Instead, shield (1200) of this example defines a gap(1210) between the interior of shield (1200) and the exterior of blade(1242), even when a clamp arm is spaced away from shield (1200) andblade (1242). This may further promote capture of vapor/fluid and/orcommunication of a cooling fluid, to assist in cooling blade (1242)and/or shield (1200), etc. Shield (1200) of this example may stilldeform and slide transversely relative to blade (1242) in a mannersimilar to shield (1100) as shown in FIG. 21B.

Still other suitable features, configurations, and operabilities forshields that may be fitted on an ultrasonic blade such as blades (42,142) will be apparent to those of ordinary skill in the art in view ofthe teachings herein.

-   -   D. Exemplary Clamp Arm Shield

In addition to or as an alternative to providing a shield for anultrasonic blade such as blades (42, 142), a shield may be provided fora clamp arm such as clamp arms (44, 144). By way of example only, FIGS.23-30 show a shield (1300) that is selectively coupled with clamp arm(144) of instrument (100). Shield (1300) of this example comprises abody (1302) with a proximal engagement feature (1304), a pair of lips(1306), and a series of openings (1308) spaced along the length of body(1302). In the present example, body (1302) is formed of a rigid plasticmaterial that is thermally insulative. Other suitable materials (e.g.,ceramic, rubber, metal with a thermally insulative coating, etc.) thatmay be used to form body (1302) will be apparent to those of ordinaryskill in the art in view of the teachings herein.

Engagement feature (1304) is configured to engage a portion of clamp arm(144) to thereby assist with seating of shield (1300) on clamp arm(144). Lips (1306) extend laterally and inwardly toward each other. Lips(1306) are configured to provide a snap fit on clamp arm (144). In otherwords, in order to secure shield (1300) to clamp arm (144), the operatormay first seat engagement feature (1304) at the proximal portion ofclamp arm (144), then pivot the distal end of shield (1300) toward thedistal end of clamp arm (144). During this movement, lips (1306) maydeflect outwardly until they clear an upper surface of clamp arm (144),at which point they snap into place over the outer regions of the uppersurface of clamp arm (144). This snap fitting may allow shield (1300) tobe replaced as needed. Of course, shield (1300) may be removably orpermanently secured to clamp arm (144) in any other suitable fashion. Itshould also be understood that shield (1300) may be an integral featureof clamp arm (144).

In the present example, body (1302) is configured to complement thecurved profile of clamp arm (144). Nevertheless, body (1302) is alsoconfigured to provide a gap between the outer surface of clamp arm (144)and the inner surface of body (1302). Openings (1308) are in fluidcommunication with this gap. These openings (1308) thus allow the flowof air and liquids into and out of the gap defined between clamp arm(144) and body (1302). It should therefore be understood that the gapand openings (1308) cooperate to provide cooling of the material formingclamp arm (144) by way of convection; while also serving as a break toinhibit conduction of heat from clamp arm (144) to body (1302) of shield(1300). In some versions, clamp arm (144) is formed of a metallicmaterial (e.g., aluminum, etc.), such that clamp arm (144) cools byconvection relatively easily.

In view of the foregoing, since shield (1300) provides a convectioncooling path and prevents tissue from contacting clamp arm (144)directly, shield (1300) may provide protection against damage to tissuethrough inadvertent contact with a hot clamp arm (144). It should beunderstood that clamp pad (146) remains exposed relative to shield(1300), such that shield (1300) does not impede the ability of endeffector (140) to clamp, cut, and seal tissue. It should also beunderstood that shield (1300) has a low profile such that shield (1300)does not impede the ability of end effector (140) to perform bluntdissections (e.g., by positioning a closed end effector (140) betweenlayers of tissue and then opening end effector (140) to separate thoselayers of tissue, etc.). Other suitable features, configurations, andproperties for shield (1300) will be apparent to those of ordinary skillin the art in view of the teachings herein.

FIGS. 30-32 show an exemplary alternative end effector (1440) with ashield (1400). End effector (1440) of this example is substantiallysimilar to end effector (40) described above. In particular, endeffector (1440) includes an ultrasonic blade (1442) and a pivoting clamparm (1444) with clamp pad (1446). Shaft assembly (1430) is substantiallysimilar to shaft assembly (30) described above. In particular, shaftassembly (1430) includes an outer sheath (1432) and an inner tube(1434). Clamp arm (1444) is pivotally coupled with outer sheath (1432)and with inner tube (1434), such that clamp arm (1444) pivots toward andaway from blade (1442) in response to translation of inner tube (1434)relative to outer sheath (1432).

Shield (1400) of the present example is secured to clamp arm (1444) by aplurality of struts (1402). By way of example only, struts (1402) may beformed as integral extensions that snap into clamp arm (1444). Othersuitable ways in which struts (1402) may be configured and coupled withclamp arm (1444) will be apparent to those of ordinary skill in the artin view of the teachings herein. Struts (1402) define a gap between theouter surface of clamp arm (1444) and the inner surface of shield(1400). The outer lateral edges (1404) of shield (1400) are also spacedaway from clamp arm (1444), such that the gap is open along the lengthof shield (1400) on both sides of shield. It should therefore beunderstood that the gap provides cooling of the material forming clamparm (1444) by way of convection; while also serving as a break toinhibit conduction of heat from clamp arm (1444) to shield (1400). Insome versions, clamp arm (1444) is formed of a metallic material (e.g.,aluminum, etc.), such that clamp arm (1444) cools by convectionrelatively easily.

In view of the foregoing, since shield (1400) provides a convectioncooling path and prevents tissue from contacting clamp arm (1444)directly, shield (1400) may provide protection against damage to tissuethrough inadvertent contact with a hot clamp arm (1444). In addition,shield (1400) may provide a substrate for condensation from steam/vaporemitted during use of end effector (1440) on tissue. In particular, thesteam/vapor may enter the gap between clamp arm (1444) and shield(1400), with condensate (1420) forming on the inner surface of shield(1400). The gathered steam/vapor may assist in cooling clamp arm (1444).In addition, at least some of the condensate (1420) that forms on theinner surface of shield (1400) may drip from shield (1400) onto clamparm (1444), providing further cooling of clamp arm (1444). In someinstances, when clamp arm (1444) is pivoted away from blade (1442), thecondensate (1420) may run proximally along the inner surface of shield(1400) and eventually drip onto blade (1442) as shown in FIG. 32,thereby providing cooling for blade (1442). Shield (1400) may thusprovide cooling of clamp arm (1444), provide cooling of blade (1442),and prevent direct contact between tissue and the outer surface of clamparm (1444).

In the present example, shield (1400) is formed of a resilient plasticmaterial that is thermally insulative. This resilience may enable outerlateral edges (1404) of shield (1400) to deflect inwardly, to therebyreduce the effective width of shield (1400), as end effector (1440) andshield (1400) are inserted through a trocar. Once end effector (1440)and shield (1400) exit the trocar, the resilience of shield (1400) maycause outer lateral edges (1404) to spring back outwardly to thepositions shown in FIGS. 30-31. Other suitable materials that may beused to form shield (1400) will be apparent to those of ordinary skillin the art in view of the teachings herein.

FIGS. 33-35 show another exemplary sleeve (3600) that may be readilysecured to clamp arm (144) of instrument (100). Sleeve (3600) of thisexample includes an open proximal end (3602) and a closed distal end(3604), such that sleeve (3600) defines a hollow interior (3608). A pairof stand-off ribs (3610) extend longitudinally through interior (3608),from open proximal end (3602) to closed distal end (3604). Sleeve (3600)is configured to fit between clamp pad (146) and clamp arm (144). Inparticular, as shown in the transition from FIG. 34A to FIG. 34B, thedistal end of clamp arm (144) may be inserted into open proximal end(3602) of sleeve (3600), such that sleeve (3600) may be slid onto clamparm (144), before clamp pad (146) is secured to clamp arm (144). Asshown in the transition from FIG. 34B to FIG. 34C, clamp pad (146) isthen secured to clamp arm (144), such that a portion of sleeve (3600) isinterposed between clamp pad (146) and clamp arm (144). In particular,and as best seen in FIG. 35, a portion of sleeve (3600) is capturedbetween a securing rail (147) of clamp pad (146) and a complementaryrecess of clamp arm (144). In the present example, sleeve (3600) is notremovable from clamp arm (144) after sleeve (3600) has been assembledwith clamp arm (144) and clamp pad (146).

As also seen in FIG. 35, standoff ribs (3610) are configured to define agap (3612) within hollow interior (3602), between clamp arm (144) andsleeve (3600). This gap (3612) may create a thermal barrier,substantially preventing conductive heat transfer from clamp arm (144)to sleeve (3600). In some versions, sleeve (3600) further includesopenings in fluid communication with gap (3612), which may providecooling of the material forming clamp arm (144) by way of convection;while also allowing fluids to reach clamp arm (144). In the presentexample, standoff ribs (3610) are simply formed by regions of thesidewall of sleeve (3600) that have a greater thickness than otherregions of sleeve (3600). By way of example only, sleeve (3600) may beformed of silicone rubber. Other suitable materials that may be used toform sleeve (3600) will be apparent to those of ordinary skill in theart in view of the teachings herein.

In view of the foregoing, since sleeve (3600) provides a convectioncooling path and/or prevents tissue from contacting clamp arm (144)directly, sleeve (3600) may provide protection against damage to tissuethrough inadvertent contact with a hot clamp arm (144). It should beunderstood that clamp pad (146) remains exposed relative to sleeve(3600), such that sleeve (3600) does not impede the ability of endeffector (140) to clamp, cut, and seal tissue. It should also beunderstood that sleeve (3600) has a low profile such that sleeve (3600)does not impede the ability of end effector (140) to perform bluntdissections (e.g., by positioning a closed end effector (140) betweenlayers of tissue and then opening end effector (140) to separate thoselayers of tissue, etc.). In some instances, clamp arm (144) hasadditional structural features (e.g., a distal tissue dissectionprotrusion, etc.). Sleeve (3600) may readily conform to such featuresand/or be made to conform to such features. Other suitable features,configurations, and properties for sleeve (3600) will be apparent tothose of ordinary skill in the art in view of the teachings herein.

Any of the shields/sleeves described above may include a visual markingindicating where the distal end of the ultrasonic blade meets the clamppad. This may facilitate positioning of the end effector when the bladeis obscured from the operator's view. In addition or in the alternative,the distal end of any of the shields/sleeves described above may includea blunt or sharp outwardly extending protrusion (e.g., similar to an eggtooth) that promotes gripping of tissue during blunt dissectionoperations. Still other suitable features, configurations, andoperabilities for shields that may be fitted on a clamp arm such asclamp arms (44, 144) will be apparent to those of ordinary skill in theart in view of the teachings herein.

-   -   E. Exemplary Blade Capture Features

FIGS. 36A-37 show an exemplary alternative end effector (1540). Endeffector (1540) of this example is substantially similar to end effector(40) described above. In particular, end effector (1540) includes anultrasonic blade (1542) and a pivoting clamp arm (1544) with clamp pad(1546). Shaft assembly (1530) is substantially similar to shaft assembly(30) described above. In particular, shaft assembly (1530) includes anouter sheath (1532) and an inner tube (1534). Clamp arm (1544) ispivotally coupled with outer sheath (1532) and with inner tube (1534),such that clamp arm (1544) pivots toward and away from blade (1542) inresponse to translation of inner tube (1534) relative to outer sheath(1532).

Clamp pad (1546) of the present example comprises a plurality of arcuatefingers (1500). Fingers (1500) of this example extend generallytransversely and are arranged in an alternating pattern along the lengthof clamp pad, such that fingers (1500) are interdigitated. Fingers(1500) are formed of a resilient material (e.g., plastic, etc.), suchthat fingers (1500) deflect outwardly and then substantially close aboutblade (1542) as clamp arm (1544) is pivoted toward blade (1542). Itshould be understood that the spaces between fingers (1500) may providewicking channels for fluids at a surgical site. In either case, wickingmay be provided through a capillary action while blade (1542) andfingers (1500) are engaging tissue. Once the tissue is released fromblade (1542) and clamp arm (1544), the wicked fluid may assist incooling blade (1542) and/or clamp arm (1544) through conduction andphase change.

In addition or in the alternative, wicking channels may be formed in theinner surfaces of fingers (1500). In one merely illustrative variation,fingers (1500) are substituted with continuous hoops that each extendfrom one lateral side of clamp pad (1546) to the other lateral side ofclamp pad (1546). Such hoops may also have spaces therebetween thatprovide wicking channels for fluids at a surgical site, which may assistin cooling blade (1542) and/or clamp arm (1544) as described above. Inaddition or in the alternative, wicking channels may be formed in theinner surfaces of the hoops. Regardless of whether fingers (1500),hoops, or some other structural features are used, the fingers (1500),hoops, or other structural features may be coated with a hydrophilicmaterial (e.g., HYDAK® T-070 or HYDAK® T-018 by Biocoat Incorporated ofHorsham, Pennsylvania) to assist in fluid retention for coolingpurposes. It should also be understood that the fingers (1500), hoops,or other structural features may serve as shields, preventinginadvertent contact between a hot blade (1542) and tissue and/or a hotclamp arm (1544) and tissue. Other suitable configurations andproperties for clamp pad (1546) will be apparent to those of ordinaryskill in the art in view of the teachings herein.

III. Miscellaneous

In addition to or as an alternative to using shielding to reduce heat ina version of instrument (10, 100), a fluid may be used to cool blade(42, 142). For instance, a cooling liquid (e.g., saline, etc.) may beapplied to the proximal end of blade (42, 142). The cooling fluid maythen be communicated distally along the rest of the length of blade (42,142) to thereby cool blade. The ultrasonic vibration of blade (42, 142)may provide such distal communication of the fluid. In some suchversions, a particular vibrational scheme may be used to drive liquiddistally along blade (42, 142). Such a particular, vibrational schememay have no meaningful effect on tissue that is in contact with blade(42, 142) while blade is being driven in such a fashion. For instance,blade (42, 142) may be vibrated in short pulses (e.g., of approximately10 to 20 millisecond duration) of low amplitude motion to drive theliquid distally along blade (42, 142). In some such instances, generator(16, 116) is programmed to provide such liquid driving ultrasonicactivation of blade (42, 142) when the operator is not pressing anybuttons (26, 126). In addition or in the alternative, generator (16,116) may be programmed to provide liquid driving ultrasonic activationof blade (42, 142) when generator (16, 116) detects that blade (42, 142)is not contacting tissue. As yet another merely illustrative example,instrument (10, 100) may include a separate user input feature that isoperable to manually trigger a liquid driving vibrational scheme. Othersuitable ways in which a liquid driving vibrational scheme may betriggered will be apparent to those of ordinary skill in the art in viewof the teachings herein.

In some other versions, the same vibrational movement that is used todrive blade during tissue cutting/sealing may drive liquid distallyalong blade (42, 142). As yet another merely illustrative example, fluidmay be communicated to and/or along blade in accordance with at leastsome of the teachings of U.S. Pub. No. 2011/0152759, entitled “Use ofBiomarkers and Therapeutic Agents with Surgical Devices,” published Jun.23, 2011, the disclosure of which is incorporated by reference herein.It should be understood that the teachings in U.S. Pub. No. 2011/0152759relating to dispensation of medical fluids may be readily adapted toprovide communication of cooling fluid. Additional examples of ways inwhich fluid may be used to cool blade (42, 142) are described in U.S.Patent App. No. [ATTORNEY DOCKET NO. END7325USNP.0616768], entitled“Features to Apply Fluid to an Ultrasonic Blade of a SurgicalInstrument,” filed on even date herewith, the disclosure of which isincorporated by reference herein; U.S. Patent App. No. [ATTORNEY DOCKETNO. END7325USNP3.0621498], entitled “Sleeve Features for UltrasonicBlade of a Surgical Instrument,” filed on even date herewith, thedisclosure of which is incorporated by reference herein; U.S. PatentApp. No. [ATTORNEY DOCKET NO. END7479USNP.0616774], entitled “Featuresto Drive Fluid toward an Ultrasonic Blade of a Surgical Instrument,”filed on even date herewith, the disclosure of which is incorporated byreference herein; U.S. Patent App. No. [ATTORNEY DOCKET NO.END7577USNP.0621500], entitled “Features for Communication of Fluidthrough Shaft Assembly of Ultrasonic Surgical Instrument,” filed on evendate herewith, the disclosure of which is incorporated by referenceherein; and U.S. Patent App. No. [ATTORNEY DOCKET NO.END7578USNP.0621502], entitled “Ultrasonic Surgical Instrument withBlade Cooling through Retraction,” filed on even date herewith, thedisclosure of which is incorporated by reference herein. It should beunderstood that the teachings herein may be readily combined with theteachings of those references and the various other references citedherein. Other examples will be apparent to those of ordinary skill inthe art in view of the teachings herein.

In some instances, the heating at an end effector (40, 140) may becaused or hastened by direct contact between clamp pad (46, 146) andblade (42, 142) while clamp arm (44, 144) is closed and blade (42, 142)is activated, etc. Such direct contact may occur at regions where tissueis not interposed between clamp pad (46, 146) and blade (42, 142). Someoperators may position tissue just between the distal portion of clamppad (46, 146) and the distal portion of blade (42, 142). This may occurwhen end effector (40, 140) is used to transect relatively smallvessels. When this occurs, the distal portions of clamp pad (46, 146)and blade (42, 142) may both contact the tissue compressed between clamppad (46, 146) and blade (42, 142); yet the proximal portions of clamppad (46, 146) and blade (42, 142) may just directly contact each other.When blade (42, 142) is activated in such instances, clamp pad (46, 146)and blade (42, 142) may rapidly generate a significant amount of heat atthe proximal portions where the direct contact occurs.

It may therefore be desirable to minimize the amount of direct contactbetween clamp pad (46, 146) and blade (42, 142), particularly at theproximal regions of clamp pad (46, 146) and blade (42, 142). In otherwords, it may be desirable to provide staged engagement between clamppad (46, 146) and blade (42, 142), such that the distal regions of clamppad (46, 146) and blade (42, 142) engage first; then the proximalregions of clamp pad (46, 146) and blade (42, 142). Various examples ofhow an end effector (40, 140) may provide such staged engagement aredescribed in U.S. Provisional Patent App. No. 61/908,920, the disclosureof which is incorporated by reference herein; and also in U.S. PatentApp. No. [ATTORNEY DOCKET NO. END7325USNP2.0616772], entitled“Ultrasonic Surgical Instrument with Staged Clamping,” filed on evendate herewith, the disclosure of which is incorporated by referenceherein. It should be understood that the teachings herein may be readilycombined with the teachings of those references and the various otherreferences cited herein. Other examples will be apparent to those ofordinary skill in the art in view of the teachings herein.

It should be understood that any of the versions of instrumentsdescribed herein may include various other features in addition to or inlieu of those described above. By way of example only, any of theinstruments described herein may also include one or more of the variousfeatures disclosed in any of the various references that areincorporated by reference herein. It should also be understood that theteachings herein may be readily applied to any of the instrumentsdescribed in any of the other references cited herein, such that theteachings herein may be readily combined with the teachings of any ofthe references cited herein in numerous ways. Other types of instrumentsinto which the teachings herein may be incorporated will be apparent tothose of ordinary skill in the art.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions of the devices described above may have application inconventional medical treatments and procedures conducted by a medicalprofessional, as well as application in robotic-assisted medicaltreatments and procedures. By way of example only, various teachingsherein may be readily incorporated into a robotic surgical system suchas the DAVINCI™ system by Intuitive Surgical, Inc., of Sunnyvale, Calif.Similarly, those of ordinary skill in the art will recognize thatvarious teachings herein may be readily combined with various teachingsof U.S. Pat. No. 6,783,524, entitled “Robotic Surgical Tool withUltrasound Cauterizing and Cutting Instrument,” published Aug. 31, 2004,the disclosure of which is incorporated by reference herein.

Versions described above may be designed to be disposed of after asingle use, or they can be designed to be used multiple times. Versionsmay, in either or both cases, be reconditioned for reuse after at leastone use. Reconditioning may include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, someversions of the device may be disassembled, and any number of theparticular pieces or parts of the device may be selectively replaced orremoved in any combination. Upon cleaning and/or replacement ofparticular parts, some versions of the device may be reassembled forsubsequent use either at a reconditioning facility, or by a userimmediately prior to a procedure. Those skilled in the art willappreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In one sterilization technique, thedevice is placed in a closed and sealed container, such as a plastic orTYVEK bag. The container and device may then be placed in a field ofradiation that can penetrate the container, such as gamma radiation,x-rays, or high-energy electrons. The radiation may kill bacteria on thedevice and in the container. The sterilized device may then be stored inthe sterile container for later use. A device may also be sterilizedusing any other technique known in the art, including but not limited tobeta or gamma radiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

1-20. (canceled)
 21. An apparatus comprising: (a) a shaft assemblyextending along a longitudinal axis; (b) an end effector located at adistal end of the shaft assembly, wherein the end effector comprises:(i) an ultrasonic blade operable to treat tissue with ultrasonic energy,and (ii) a clamp arm operable to clamp tissue against the ultrasonicblade; and (c) a shield member positioned to cover at least a portion ofthe ultrasonic blade, wherein the shield member and the ultrasonic bladeextend distally together along a curved path that deflects laterallyaway from the longitudinal axis.
 22. The apparatus of claim 21, whereinthe ultrasonic blade includes a first blade side that faces the clamparm and a second blade side opposed from the first blade side, whereinthe shield member is positioned to cover at least a portion of thesecond blade side.
 23. The apparatus of claim 22, wherein the shieldmember is positioned to define a gap between the second blade side andan inner side of the shield member, wherein the gap is sized to receivefluid for cooling the ultrasonic blade.
 24. The apparatus of claim 22,wherein the shield member extends circumferentially about the ultrasonicblade so as to define an elongate opening, wherein the elongate openingis configured to expose the first blade side for treating tissue. 25.The apparatus of claim 24, wherein the elongate opening extends alongthe curved path.
 26. The apparatus of claim 21, wherein the ultrasonicblade extends through the shield member.
 27. The apparatus of claim 21,wherein the shield member is longitudinally fixed relative to the shaftassembly.
 28. The apparatus of claim 27, wherein a distal end of theshield member is positioned distal to a distal end of the ultrasonicblade.
 29. The apparatus of claim 27, wherein a distal end of the shieldmember is positioned proximal to a distal end of the ultrasonic blade.30. The apparatus of claim 21, wherein the shield member includes aproximal hub and a shielding portion extending distally from theproximal hub, wherein the proximal hub encircles the ultrasonic blade.31. The apparatus of claim 30, wherein the proximal hub includes a pairof tabs configured to secure the shield member relative to the shaftassembly.
 32. The apparatus of claim 30, wherein the shaft assemblycomprises an outer sheath and a cap fixed to a distal end of the outersheath, wherein the proximal hub is received within the cap.
 33. Theapparatus of claim 21, wherein the shield member includes a plurality ofteeth.
 34. The apparatus of claim 21, wherein the shield member tapersdistally.
 35. The apparatus of claim 21, further comprising a shankpivotably coupled with the shaft assembly, wherein the clamp arm issecured to the shank.
 36. An apparatus comprising: (a) a shaft; (b) anend effector located at a distal end of the shaft, wherein the endeffector comprises: (i) an ultrasonic blade operable to treat tissuewith ultrasonic energy, and (ii) a clamp arm operable to clamp tissueagainst the ultrasonic blade; and (c) a shield member, wherein theshield member is fixed relative to the shaft and extendscircumferentially about the ultrasonic blade, wherein the shield memberincludes an elongate opening that faces toward the clamp arm and exposesa portion of the ultrasonic blade for engagement with tissue.
 37. Theapparatus of claim 36, wherein the shield member comprises a proximalportion and a distal portion, wherein the proximal portion encircles theultrasonic blade, wherein the elongate opening is formed in the distalportion.
 38. The apparatus of claim 36, wherein the shield member andthe ultrasonic blade extend distally together along a curved path. 39.An apparatus comprising: (a) a shaft; (b) an end effector located at adistal end of the shaft, wherein the end effector comprises: (i) anultrasonic blade operable to treat tissue with ultrasonic energy, (ii) aclamp arm movable relative to the ultrasonic blade, wherein the clamparm includes an inner clamp arm side and an outer clamp arm side, and(iii) a clamp pad coupled with the inner clamp arm side, wherein theclamp pad is configured to compress tissue against the ultrasonic blade;and (c) a shield member, wherein the shield member covers at least aportion of the outer clamp arm side so as to define a gap between theouter clamp arm side and an inner side of the shield member, wherein theshield member includes at least one opening that extends fully through athickness of the shield member and fluidly communicates with the gap.40. The apparatus of claim 39, wherein the at least one opening includesa plurality of openings arranged along a length of the shield member.